Selective switching mechanism



Aug. 5 1924.

J. ERICKSON SELECTIVE SWITCHING MECHANISM Filed March 28. 1921 2 Sheets-Sheet 1 Jmhn Erwksnn HIT;

SELECTIVE SWITCHING MECHANISM Filed March 28, 192) 2 Sheets-Sheet 2 fnuanlnr 621m Ericksm Patented Aug. 5, 1924.

UNITED STATES PATENT QFFICE.

JOHN ERICKSON, OF CHICAGO, ILLINCIS, ASSIGNOR TO AUTOMATIC ELECTRIC COM- PANY, OF CHICAGO, ILLINOIS,

A CORPCE-ATIQN OF ILLINOIS.

SELECTIVE SWITCHING DIECHAIIISM.

Application filed March 28, 1921. Serial 110.456,.338.

To all whom it may concern:

Be it known that 1, JOHN ERICKSON, a citizen of the United States of America, and a resident of Chicago, Cook County, and State of Illinois, have invented certain new and useful Improvements in Selective Switching Mechanisms, of which the following is a specification.

The present invention relates in general to selective switching mechanism, and more particularly to selective switching mechanism for use in automatic telephone systems.

More specifically, the invention relates in the provision of a new and improved switch structure for automatic switches of the Strowger type. One of the objects of the invention is to provide a new and improved off normal interrupter spring bracket which exceedingly simplifies the casting of the switch frame and at the same time renders it more substantial.

Another object is to provide in a switch of the above character a new type of vertical ratchet teeth which enables the switch to be more easily adjusted.

It will be understood that these improvements in switch structure are readily applicable to either connector or selector switches though, in order to facilitate the description, they have been shown applied to a selector switch. These and other objects of the invention will be described fully hereinafter with reference to the accompanying drawings.

Referring now to the drawings: In Fig. 1 is shown a side elevation of a selector switch embodying the improvements.

In Fig. 2 is shown a front elevation of the same.

7 Figs. 3 and 1, respectively, show detailed views of the improved 01f normal and interrupter spring bracket, first in a side view and then in a front View.

Fig. 5 shows a portion of the switch shaft and is intended to supplement Fig. 2 in illustrating the construction of the vertical ratchet teeth.

Referring to the drawings, the construction of a selector-switch embodying the new improvements will now be discussed in detail. For this purpose the operation of the switch will first be briefly explained with reference tocFigs. 1 and 2. The vertical magnet 100 is adapted, when opera ed, to raise the switch shaft step by step by means of armature 105 through the medium of the vertical pawl 107 engaging the vertical ratchet teeth 110. Each time the vertical armature. 105 is operated a projection 100 thereon raises the release link 132, so that upon the first operation of the vertical armature the release link allows the double dog 109 to release. The Vertical dog 103 then engages the toothed insert 111, thereby maintaining the switch shaft 104 in its vertically operated position throughout its vertical movement. Upon the first vertical step of the switch shaft, the off normal springs 135 are also operated.

When the rotary magnets 101 are operated the switch shaft 104 is rotated by means of the rotary magnet armature 115 through the medium of the rotary pawl 112 engaging the rotary ratchet teeth 121. Upon the first rotary step of the switch shaft st the stationary dog 125. which hitherto was riding in the slot 126, engages the vertical ratchet teeth, thereby maintaining the switch shaft 10% in its vertically operated position during rotation. hen the switch shaft is rotated one step the vertical dog 108 no longer engages the toothed insert 111, and thus the rotary dog 13% is rendered free to perform its function of maintaining the switch shaft in the position to which it is rotated. It will be noted that the finger arm 118 attached to the armature 115 of the rotary magnet operates the break springs 120 each time the: rotary magnet is operated. lVhen the switch shaft is rotated into its last rotary position, that is, on the eleventh step, the cam 1 13 operates the springs 14 1.

In order to release the switch the release magnet 130 is operated. When this occurs the armature 131 is attracted and the pin 137 thereupon forces the double dog 109 out of engagement with the switch shaft. The double dog is held in this position, as the back projection 139 thereon is engaged by the release link 132. Immediately upon the rotary dog being forced out of engagement with the rotary teeth the shaft returns to its normal rotary position under the control of the cup spring 133. Then this occn rs the stationary dog again rides in the slot 126, and the shaft falls to normal. by its own weight thereby opening the off normal springs 135.

Referring now particula y to Figs. 3, 4

and the particular improvements in switch structure will be described somewhat more in detail. The switch bracket shown in Figs. 3 and l in a side and front view, respectively, is made of cold rolled steel and has therefore a high tensile strength. The lug 140 which carries the rotary pawl guide 119 is formed as an integral part of this bracket. Besides this, the bracket serves as a mounting for the off normal and rotary interrupter springs. The stationary dog 125 and the stop 138 for controlling the movement of the vertical pawl also forms part of this bracket. Hitherto the lug 140 was cast with the switch frame thereby rendering the casting complicated and expensive. By removing this lug from the switch frame proper and placing it on the interrupter and off normal spring bracket it will be apparent that the casting of the switch frame is greatly simplified and at the same time this part which hitherto was often fragile and liable to breakage is rendered stronger and more substantial. The bracket, it will be noted, is placed in such a position on the switch frame that the casting itself is materially strengthened. Another advantage of this structure is that the bracket may be readily removed from the switch frame thus enabling the off normal and interrupter springs to be easily replaced and adjusted. In addition to the above, when the bracket is removed the various parts of the switch are rendered more accessible for repairs and adjustments.

In 5 is shown a detailed view of the improved selector shaft in an operated positi on. It will be noted that there is a toothed member or insert 111 which is set in a slot cut through the vertical teeth of the switch shaft. This member is made of hard steel and is slightly larger than the slot, in which it is forced under pressure and is held by friction. By the provision of the toothed insert 111 the adjustments of the various dogs in relation to the switch shaft are more readily attained. while at the same time the means employed is simple and capable of being manufactured at a low cost. The improvement in the process of adjusting the dogs will be readily appreciated from a brief explanation of the old method. WVith the type of shaft used former y, the stationary dog was adjusted somewhat higher than the vertical dog so that upon the first rotary step of the switch shaft the shaft was slightly raised, whereupon the vertical dog no longer engaged the vertical ratchet teeth and the rotary dog was enabled to perform its functions. It will be appreciated that in the above procedure these parts needed a very nice adjustment. These same results are now obtained more easily and in a much more atisfactory manner by adding the raised toothed member 111 to the shaft, for the reason that immediately upon the first rotary step of the switch the toothed insert is rotated away from the vertical dog and the latter is left entirely free. Thus it will be apparent that a delicate adjustment of the various dogs in relation to the vertical ratchet teeth is unnecessary for proper operation.

Having fully described and ascertained the features of the invention what is considered. to be new and desired to have protected by Letters Patent will be pointed out in the appended claims.

hat I claim as my invention is:

1. In an automatic switch, a rectangular cast metal frame, a shaft supported outside said frame, an operating magnet mounted inside the frame, one side member of the frame being cut away to permit control of the shaft by the armature of said magnet, and a bracket of non-brittle metal secured to said frame so as to bridge the cut away portion thereof and reduce the liability of breakage.

2. In an automatic switch, a rectangular cast metal frame, a shaft supported outside said frame, an operating magnet mounted inside the frame, one side member of the frame being cut away to permit control of the shaft by the armature of said magnet, and bracket of cold rolled steel attached to the recessed side member at a plurality of points so as to serve as a. reinforcing member.

3. In an automatic switch, a rectangular cast metal frame, a shaft supported outside said frame, an operating magnet mounted inside the frame, one side member of the frame being cut away to permit control of the shaft by the armature of said magnet, a bracket of non-brittle metal secured to said frame so as to bridge the cut away portion thereof and reduce the liability of breakage, and auxiliary shaft controlling attachments supported on said bracket.

41-. In an automatic switch, a rectangular cast metal frame, a shaft supported outside said frame, an operating magnet mounted inside the frame, one side member of the frame being cut away to permit control of the shaft by the armature of said magnet, a bracket of cold rolled steel attached to the recessed side member at a plurality of points so as to serve as a reinforcing member, and auxiliary shaft controlling attachments supported on said bracket.

5. In an automatic switch, a vertical and rotary shaft, a series of circular ratchet teeth concentric with said shaft, an offset for each tooth whereby a second series of teeth is produced, lying outside the plane of the first series, a detent for engaging the second series of teeth during the vertical m ement of the Shaft, and. a de nt f9? ea gaging the first series of teeth during the rotary movement.

6. In an automatic switch, a vertical and rotary shaft, a series of circular ratchet teeth concentric with said shaft and a dog for engaging said teeth,a rack member attached. to the shaft, teeth on said rack member corresponding to said circular teeth but located further from the center of the shaft, and a detent for engaging said last named teeth.

7 In an automatic switch, a vertical and rotary shaft, a series of circular ratchet teeth concentric with said shaft, a dog for engaging said teeth during the rotary move ment of the shaft, a vertical detent adjacent said circular teeth but incapable of engaging the same, and a toothed member on said shaft cutting said circular teeth at right angles and having teeth which project be yond the said circular teeth so as to be engaged by said vertical detent.

8. In an automatic switch, a shaft, operating magnets for first raising said shaft vertically and for then rotating it, a double dog comprising vertical and rotary detents, a stationary dog, and three separate sets of ratchet teeth on said shaft engaged by said detents and stationary dog, respectively, to support said shaft during the operation thereof.

9. In an automatic switch, a shaft, operating magnets for raising said shaft vertically and for rotating it, a double dog comprising vertical and rotary detents, a stationary dog, ratchet teeth engaged by the vertical detent during the vertical movement, separate ratchet teeth engaged by the stationary dog during the rotary movement, and ratchet teeth engaged by the rotary detent during the rotary movement.

10. In an automatic switch, a vertical and rotary shaft, a series of circular ratchet teeth concentric with said shaft, a second. series of ratchet teeth, means for driving said shaft vertically, a detent for engaging said second series of teeth during the vertical movement, means for rotating said shaft and both series of teeth, the second series being moved by the rotary movement out of operative relation to said detent, and a second detent for engaging a tooth in said first series during the rotary movement to support the shaft in its operated position.

11. In an automatic switch, a vertical and rotary shaft, a series of vertical ratchet teeth, a suitable detent adapted to cooperate with said teeth while said shaft is driven vertically, means for rotating said shaft, whereby said vertical ratchet teeth are moved out of operative relation with said detent, a second series of vertical ratchet teeth, and a second detent for engaging a tooth of said second series to support the shaft during its rotary movement.

12. In an automatic switch, a shaft having' a plurality of series of teeth, pawls for said switch adapted to engage said teeth to move said shaft in a vertical direction and to rotate the same, a plurality of auxiliary teeth, there being one auxiliary tooth associated with each vertical tooth, a double dog, one element of said dog co-operating with said auxiliary teeth only during the vertical movement of the shaft, and the other element engaging another of said series of teeth only during the rotary move ment, and another dog for supporting the shaft in place of said first element after the rotary movement starts.

In witness whereof, I hereunto subscribe my name this 18th day of March, A. 1).,

JOHN ERIGKSON. 

